Table Of Content

PLANT AND SOIL Contents Volume 216, Nos. 1-2 1999 Potassium content in soil, uptake in plants and the potassium balance in three European long-term field experiments L. Blake, S. Mercik, M. Koerschens, K.W.T. Goulding, S. Stempen, A. Weigel, P.R. Poulton and D.S. Powison Modelling the effect of active roots on soil organic matter turnover P. Bottner, M. Pansu and Z. Sallih Effects of aluminium on canola roots T.S. Clune and L. Copeland The effects of nitrogen fertilisation and elevated CO, on the lipid biosynthesis and carbon isotopic discrimination in birch seedlings (Betula pendula) Y. Huang, G. Eglinton, P. Ineson, R. Bol and D.D. Harkness Effect of vanadium on the growth of soybean seedlings J.F. Wang and Z. Liu Metal uptake by plants from sludge-amended soils: caution is required in the plateau interpretation R.E. Hamon, PE. Holm, S.E. Lorenz, S.P McGrath and TH. Christensen Relationships between dynamics of nitrogen uptake and dry matter accumulation in maize crops. Determination of critical N concentration D. Plénet and G. Lemaire Growth and nitrogen nutrition of Chinese fir seedlings exposed to nutrient loading and fertilization X. Xu and V.R. Timmer Effect of salinity on the association between root symbionts and Acacia cyanophylla Lind.: growth and nutrition A. Hatimi Effects of aluminium treatment on Norway spruce roots: Aluminium binding forms, element distribution, and release of organic substances A. Heim, J. Luster, |. Brunner, B. Frey and E. Frossard 103-116 Accurate root length measurement by image analysis K. Kimura, S. Kikuchi and S.-i. Yamasaki 117-127 Effects of leguminous ground cover competition on red birch and soil nutrient status in the nursery K. Hanninen, R. Ohtonen and S. Huttunen 129-138 Long-term effects of nitrate on lucerne (Medicago sativa L.) nitrogen fixation is not influenced by the denitrification status of the microsymbiont J.l. Garcia-Plazaola, A. Hernandez, J.M. Becerril and C. Arrese-Igor 139-145 NaCl induced changes in ionically bound peroxidase activity in roots of rice seedlings C. Chi Lin and C. Huei Kao 147-153 Rhizodeposition and C-partitioning of Lolium perenne in axenic culture affected by nitrogen supply and defoliation E. Paterson and A. Sim 155-164 Nitric oxide flux from soil during the growing season of wheat by continuous measure- ments of the NO soil-atmosphere concentration gradient: A process study A. Gut, A. Neftel, T. Staffelbach, M. Riedo and B.E. Lehmann 165-180 Author index 181 Instructions for authors 183-188 Cover Photo: An aerial view of the Broadbalk Classical Experiment at Rothamsted Experimen- tal Station, Harpenden, UK. The oldest, continuous field experiment, begun in 1843 to test vari- ous manurial treatments on winter wheat. Since 1968 a crop rotation of potatoes, wheat and a fal- low season has been incorporated on some plots. Plot 3, the fourth strip from the right of the photo- graph, has received no nutrient inputs, apart from those derived from atmospheric deposition, since 1843 Plant and Soil Vol. 216, pp. 1-14. ÀB ;E R rGiEse x